Method and apparatus for parallel transfer of blocks of data between an interface module and a non-volatile semiconductor memory

ABSTRACT

A system including a non-volatile semiconductor memory (NVSM), an interface module and a control module. The NVSM stores first and second blocks of data. The first or second block of data is non-page based such that a size of the first block of data or a size of the second block of data is not an integer multiple of a page of data. The interface module transfers the first and second blocks of data during respectively a first data transfer event and a second data transfer event. The control module, based on descriptors, controls the first and second data transfer events such that the interface module transfers the first block of data between the interface module and the NVSM while transferring the second block of data between the interface module and the NVSM. The descriptors include respective sets of instructions for transferring the first and second blocks of data.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present disclosure is a continuation of U.S. patent application Ser. No. 13/166,340 (now U.S. Pat. No. 8,868,852) filed on Jun. 22, 2011. This application claims the benefit of U.S. Provisional Application No. 61/362,251 filed on Jul. 7, 2010. The entire disclosures of the applications referenced above are incorporated herein by reference.

FIELD

The present disclosure relates to non-volatile semiconductor memory access systems, and more particularly to data transfer control systems for non-volatile semiconductor memory.

BACKGROUND

The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent the work is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.

A non-volatile semiconductor memory (NVSM) drive (e.g., a flash drive) includes NVSM and operates based on a size of a page of data. For example, data transferred to and from the NVSM is grouped into data sets. Each of the data sets has a length equal to the length of one or more pages of data. A page of data may have a length of, for example, 8 kilobytes (KB).

A NVSM drive may include, for example, an NVSM interface, a buffer managing module, an error correction code (ECC) module, an interface management module and a NVSM. The NVSM interface may communicate with a host. Data is transferred between the NVSM interface and the host. The buffer managing module receives data from the host prior to being stored in the NVSM and receives data from the NVSM prior to being transferred to the host. The ECC module encodes data provided to the NVSM and decodes data received from the NVSM. The interface management module controls data transfers between the ECC module and the NVSM.

The NVSM control module generates descriptors in response to access request signals received from the host. The descriptors may indicate, for example, whether a read operation or a program (i.e. write) operation is to be performed, the amount of data to be transferred, and the addresses to access in the NVSM. The ECC module and the interface management module are operated based on the descriptors.

The interface control module communicates with the NVSM via multiple channels (e.g., 8 channels per NVSM chip) and includes a first-in-first-out (FIFO) register for each of the channels. The FIFO registers are accessed sequentially during read and program operations. The size of each of the FIFO registers is equal to the size of one or more pages of data.

During a program operation, the ECC module transfers data in a page-based format to the interface control module prior to being stored in the NVSM. The ECC module may transfer one or more pages (M pages) of data to each of the FIFO registers, where M is an integer greater than or equal to 1. The number of pages the ECC module transfers to each of the FIFO registers is dependent on the page format of that NVSM drive. For each set of M pages transferred a single descriptor is generated.

For example, if the ECC module is operating in an NVSM drive with a single page format, 1 page of data is transferred to each of the FIFO registers. In this example, the size of each of the FIFO registers is equal to the size of 1 page of data. If the ECC module is operating in an NVSM drive with a dual page format, then 2 pages of data are transferred to each of the FIFO registers and the size of each of the FIFO registers is equal to the size of 2 pages of data. The M pages of data are transferred to a current FIFO register prior to transferring data to a next (or subsequent) FIFO register. The above-described data transfers are performed in reverse for a read operation.

Because data is not transferred to a next FIFO register until a current FIFO register receives the M pages of data, data transfer delays can result. These delays may be experienced at one or more of the FIFO registers and can increase with higher order page formats. The order of a page format refers to the number of pages transferred during a single data transfer event. A data transfer event refers to transferring data to or from one of the channels of the NVSM. For example, in a NVSM drive with a 2-page format, if a “bottleneck” arises at a first FIFO register due to speed differences between the ECC module and a first channel, delays can arise at the first FIFO register and at all subsequent FIFO registers. Since two pages of data are transferred to a single FIFO register, a second page of data can be delayed when a first page of data is delayed. Also, delays in transferring the second page of data to the first FIFO register delays transfers of data to FIFO registers subsequent to the first FIFO register.

SUMMARY

A control system is provided and includes a control module configured to control data transfer events of blocks of data between an interface management module and a non-volatile semiconductor memory based on at least two descriptors for each one of the data transfer events. The non-volatile semiconductor memory is prepared for a read event or a program event of the data transfer event. The interface management module and the non-volatile semiconductor memory are configured to operate within a solid-state memory drive. A command management module is configured to generate a parameter signal based on the at least two descriptors. The interface management module is configured to generate instruction signals based on the parameter signal and transmit the instruction signals to the non-volatile semiconductor memory to perform the read event or the program event.

In other features, each of the data transfer events includes transferring a page of data. A size of the page of data is equal to a size of at least two of the blocks of data. The at least two of the blocks of data is transferred based on a respective one of the at least two descriptors.

In other features, each of the data transfer events includes transferring pages of data. In other features, the interface management module is configured to generate trigger instructions sets for each of the data transfer events to initiate transfer of the blocks of data.

In other features, a number of the at least two descriptors is equal to a number of trigger instruction sets generated for each of the data transfer events. In other features, the interface management module is configured to generate the trigger instruction sets prior to preparing periods for each of the data transfer events. Subsequent to the preparing periods, the interface management module is configured to generate read instruction sets or program instruction sets. Each of the data transfer events includes at least one of the trigger instruction sets and at least one of the read instruction sets or the program instruction sets.

In other features, each of the at least two descriptors indicates allocation block sizes, addresses of the non-volatile semiconductor memory, and whether the data transfer events are read, program or erase events.

In other features, bits of the parameter signal indicate an amount of data to transfer, addresses of the non-volatile semiconductor memory and whether the data transfer events are read, program or erase events.

In other features, the parameter signal is a first parameter signal. The command management module is configured to generate a second parameter signal based on the at least two descriptors. An error correction code module is configured to transfer blocks of data to and from the interface management module based on the second parameter signal

In other features, the interface management module includes first-in-first-out registers. The error correction code module is configured to spread the blocks of data to the first-in-first-out registers. The size of each of the first-in-first-out registers is less than a size of a page of data.

In other features, a solid-state memory drive is provided and includes the control system, a buffer managing module and an error correction code module. The buffer managing module is configured to receive host data sectors from a host in communication with the solid-state memory drive, generate first drive data sectors based on the host data sectors, receive second drive data sectors, and transmit host data sectors to the host. The error correction code module is configured to transfer the first drive data sectors to from the buffer managing module to the interface management module and transfer the second drive data sectors from the interface management module to the buffer managing module.

Further areas of applicability of the present disclosure will become apparent from the detailed description, the claims and the drawings. The detailed description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the disclosure.

BRIEF DESCRIPTION OF DRAWINGS

The present disclosure will become more fully understood from the detailed description and the accompanying drawings, wherein:

FIG. 1 is a functional block diagram of a NVSM storage system incorporating an interface management control system according to the present disclosure;

FIG. 2 is a functional block diagram of a portion of the interface management control system according to the present disclosure;

FIG. 3 is a timing diagram illustrating a single page read event for a page based transfer according to the present disclosure;

FIG. 4 is a timing diagram illustrating a single page program event for a page based transfer according to the present disclosure;

FIG. 5 is a timing diagram illustrating a multi-page read event using multiple descriptors according to the present disclosure;

FIG. 6 is a timing diagram illustrating a multi-page program operation using multiple descriptors according to the present disclosure;

FIG. 7 is a functional block diagram of a portion of an interface management control system illustrating multi-page program events with page-sized transfers according to the present disclosure;

FIG. 8 is a timing diagram illustrating a read event with the same number of descriptors as allocation blocks transferred according to the present disclosure;

FIG. 9 is a timing diagram illustrating a read event with more descriptors than allocation blocks transferred according to the present disclosure;

FIG. 10 is a timing diagram illustrating a multi-allocation block read event with multiple instruction sets according to the present disclosure;

FIG. 11 is a timing diagram illustrating a program event with the same number of descriptors as allocation blocks transferred according to the present disclosure;

FIG. 12 is a timing diagram illustrating a program event with more descriptors than allocation blocks transferred according to the present disclosure;

FIG. 13 is a timing diagram illustrating a multi-allocation block read event with multiple instruction sets according to the present disclosure;

FIG. 14 is a functional block diagram of a portion of an interface management control system illustrating an allocation block based program events with allocation block sized transfers according to the present disclosure;

FIG. 15 is a functional block diagram of a portion of an interface management control system incorporating multiple encoders and decoders according to the present disclosure; and

FIG. 16 illustrates a method of operating a NVSM storage system and a NVSM drive according to the present disclosure.

DESCRIPTION

The following description is merely illustrative in nature and is in no way intended to limit the disclosure, its application, or uses. For purposes of clarity, the same reference numbers will be used in the drawings to identify similar elements. As used herein, the phrase at least one of A, B, and C should be construed to mean a logical (A or B or C), using a non-exclusive logical OR. It should be understood that steps within a method may be executed in different order without altering the principles of the present disclosure.

As used herein, the term module may refer to, be part of, or include an Application Specific Integrated Circuit (ASIC); an electronic circuit; a combinational logic circuit; a field programmable gate array (FPGA); a processor (shared, dedicated, or group) that executes code; other suitable components that provide the described functionality; or a combination of some or all of the above, such as in a system-on-chip. The term module may include memory (shared, dedicated, or group) that stores code executed by the processor.

The term code, as used above, may include software, firmware, and/or microcode, and may refer to programs, routines, functions, classes, and/or objects. The term shared, as used above, means that some or all code from multiple modules may be executed using a single (shared) processor. In addition, some or all code from multiple modules may be stored by a single (shared) memory. The term group, as used above, means that some or all code from a single module may be executed using a group of processors. In addition, some or all code from a single module may be stored using a group of memories.

The apparatuses and methods described herein may be implemented by one or more computer programs executed by one or more processors. The computer programs include processor-executable instructions that are stored on a non-transitory tangible computer readable medium. The computer programs may also include stored data. Non-limiting examples of the non-transitory tangible computer readable medium are nonvolatile memory, magnetic storage, and optical storage.

Although the terms first, second, third, etc. may be used herein to describe various elements, components, channels, modules, and/or devices, these elements, components, channels, modules, and/or devices should not be limited by these terms. These terms may be only used to distinguish one elements, components, channels, modules, and/or devices from another elements, components, channels, modules, and/or devices. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first elements, components, channels, modules, and/or devices discussed below could be termed a second elements, components, channels, modules, and/or devices without departing from the teachings of the example embodiments.

In the following description, the term “non-volatile semiconductor memory (NVSM)” may refer to phase change memory (PCM), electrically erasable programmable read-only memory (EEPROM), read only memory (ROM) and/or random access memory (RAM). A couple of examples of EEPROM are NAND flash memory and NOR flash memory.

Also, in the following description the term “host” may refer to a device that transfers data to and/or accesses data from a NVSM drive. A NVSM drive may be a flash drive, a universal serial bus (USB) drive, a solid-state memory drive, etc.

As a few examples, a host may refer to a computer, a camera, a handheld device, a portable device, a cellular phone, a printer, a personal data assistant, an electronic note pad, a television, a display, an appliance, a monitoring system, etc. Examples of computers are a desktop computer, a laptop computer, an electronic note pad, etc. Examples of appliances are a washer, a dryer, a refrigerator, etc. A NVSM drive includes NVSM and may not include a rotating magnetic storage medium, such as a hard disk drive platter. Examples of monitoring systems include burglar monitors, smoke detection systems, baby monitors, etc.

In addition, various system elements, such as modules, network devices, and circuit components are disclosed herein. Examples of arrangements of the system elements are disclosed and include adjacent elements and non-adjacent elements. The adjacent elements are shown as being directly connected to each other. The non-adjacent elements are shown as being indirectly connected to each other.

Because there are numerous implementations of the present disclosure, the arrangements do not explicitly show all of the implementations. For example, the adjacent and non-adjacent elements shown in, for example, FIGS. 1, 2, 7, 14 and 15 may be directly or indirectly connected to each other. The adjacent and non-adjacent elements may wirelessly communicate with each other and/or may communicate with each other via wired links. The wireless communication may include Bluetooth devices and/or satisfy, for example, IEEE standards 802.11, 802.11a, 802.11b, 802.11g, 802.11h, 802.11n, 802.16, and 802.20.

In FIG. 1, a non-volatile semiconductor memory (NVSM) storage system 10 is shown. The NVSM storage system 10 includes a host 12 (or host side) and a NVSM drive 14 (or NVSM side). The host 12 includes a host control module 16 and a host interface 18. The NVSM drive 14 communicates with the host 12 via a NVSM drive interface 20. The NVSM drive 14 includes the NVSM drive interface 20, a receive path 22, a transmit path 24, an interface management control system 26 and a NVSM 28. The NVSM drive interface 20 communicates with the host interface 18. The receive and transmit paths 22, 24 transfer data between the NVSM drive interface 20 and the NVSM 28. The interface management control system 26 includes a NVSM control module 27. The NVSM control module 27 controls data transfers to and from the NVSM 28.

The interface management control system 26 operates based on predetermined, selected, and/or determined size(s) of allocation blocks of data (or allocation units (AUs)). This is unlike traditional NVSM drives that operate based on a single fixed block size. In a traditional NVSM, the single block size is equal to the size of a page of data.

In the present disclosure, an allocation block of data refers to an amount of data (or size boundary) set by the NVSM drive 14 and used to transfer data between devices and/or modules of the NVSM drive 14. Each data transfer event to and from the NVSM 28 includes one or more allocation blocks of data. The data transfer events may be program events or read events. The sizes of the allocation blocks may be the same or different: for different read events; for different program events; and/or between read events and program events. The sizes of the allocation blocks may be determined, set and/or adjusted by the NVSM control module 27. Allocation blocks, allocation block sizes and the transfer of allocation blocks are further described below.

The host control module 16 transmits and receives host data to and from the NVSM drive 14 via the host interface 18. This may include read, write (or program), and erase access events. The host 12 may generate HDSs based on a received data object and/or request host data sectors (HDSs) from the NVSM drive 14. A HDS may be the smallest length data element that is transmitted from the host 12 to the NVSM drive 14. The HDSs are transmitted between respective ports of the interfaces 18, 20. The interfaces 18, 20 may be, for example, serial advanced technology attachment (SATA) interfaces, small computer system interfaces (SCSIs), serial-attached SCSIs (SASs), fiber channel interfaces, universal serial bus (USB) interfaces, etc.

The host control module 16 may also generate access request signals 30, such as data program signals, data read signals, data erase signals, etc. The access request signals 30 may be received by a NVSM control module 27 and/or by other modules of the NVSM drive 14 via the NVSM drive interface 20. The NVSM control module 27 controls access to the NVSM 28 based on the access request signals 30. The NVSM drive 14 receives the HDSs via the NVSM drive interface 20. The NVSM control module 27 may access and/or request drive data sectors (DDSs) from the NVSM 28 based on the access request signals 30.

The receive path 22 includes a compression module 40, an encryption module 42, a buffer managing module 44, a drive data sector (DDS) generating module 46, an error correction code (ECC) module 48, an interface management module 50 and the NVSM 28. The transmit path 24 includes the NVSM 28, the interface management module 50, the ECC module 48, a HDS generating module 52, the buffer managing module 44, a decryption module 54 and a decompression module 56. The buffer managing module 44 and the DDS and HDS generating modules 46, 52 may be combined to form a single module. The interface management control system 26 includes the NVSM control module 27, a command management module 60, the ECC module 48, and the interface management module 50. Modules of the NVSM drive 14 may be referred to as a NVSM storage system.

The NVSM drive interface 20 may receive a single data stream or multiple concurrent parallel data steams from the host interface 18. The data streams may be transferred to the compression module 40. Multiple concurrent parallel data streams may be received when the host and NVSM interfaces 18, 20 are, for example, SAS interfaces.

The compression module 40 compresses HDSs received from the host interface 18 when possible and prior to being received by the buffer managing module 44. The compression is performed on HDSs that are the same length as the HDSs received from the host interface 18. The compression module 40 may use lossy and/or lossless compression methods. Lossy compression and decompression provides data that is close but not the same as the original data after compression and decompression. Lossless compression and decompression provides reconstruction of the same data as the original subsequent to compression and decompression. Lossless data compression includes detecting repeating bit patterns and removing the redundancy.

The compression module 40 compresses host data sectors (HDSs) received from the host 12 when possible. The HDSs may be uncompressed, partially compressed, and/or fully compressed when received. An HDS may be the smallest length data element that is transmitted from the host 12 to the NVSM drive 14. Certain HDSs may not be compressible, for example, when lossless compression is used and a corresponding data pattern does not include redundancy.

The encryption module 42 encrypts the compressed HDSs. The encryption module 42 encrypts data received from the compression module 40. The encryption may include one or more public and private keys. The encryption may also include one or more keys that are specific to the NVSM drive 14 or a component of the NVSM drive 14, such as a key specific to the NVSM control module 27 and/or the NVSM 28.

The buffer managing module 44 stores the HDSs in a buffer 70 and forwards the HDSs to the DDS generating module 46. The buffer 70 may include volatile memory, such as RAM, dynamic RAM (DRAM), and/or static RAM (SRAM). The buffer managing module 44 may collect and store one or more HDSs prior to storage in the NVSM 28.

The buffer managing module 44 may: convert received DDSs from the encryption module 42 to HDSs when possible; receive HDSs from a component downstream from the buffer managing module 44 (between the buffer managing module 44 and the NVSM 28); and/or transfer HDSs to the decompression module 56. Each of the DDSs may be larger than or equal to the size of the HDSs. Decompressed HDSs are transmitted to the host 12. The buffer managing module 44 may combine and store the compressed and/or encrypted HDSs in a predetermined order regardless of the order in which the HDSs are received.

For example, HDSs may be received in a numerical order or may be received in a different order. Sequentially received HDSs may be stored in different HDS registers 72 to allow for reordering of the HDSs in a numerical or predetermined order. Thus, HDS registers 72 may be used to provide HDS sets 74 for respective DDSs (HDS registers 1-N and HDS sets 1-N are shown). As a HDS register is filled and/or a predetermined DDS length limit is met, an HDS set may be released from the buffer managing module 44 and passed to the DDS generating module 46. A predetermined DDS length limit is met, for example, when no further HDSs can be and/or are to be combined with other HDSs of a current DDS.

The DDS generating module 46 generates DDSs based on the combined and/or stored HDS(s) in the HDS registers 72 and based on HDS and DDS information. The DDS generating module 46 converts the HDSs to DDSs prior to storage in the NVSM 28. The HDS and DDS information may be received from the buffer managing module 44. The HDS and DDS information may include the HDS information bits and DDS information, such as DDS length, DDS bit slot availability, etc.

The DDS generating module 46 may generate each DDS to have the same bit length. Nuisance data refers to data that is added to one or more HDSs such that a generated DDS is of a predetermined bit length. Compressed HDSs may have different bit lengths. Different amounts of nuisance data is added to combine compressed HDSs to generate DDSs of equal length. The NVSM control module 27 prevents an HDS from being split between two DDSs by adding the nuisance data. Instead of storing portions of a HDS with two or more other HDSs, nuisance data is attached. The nuisance data may include, for example, all 0's, all 1's, null states, and/or redundant data to minimize programming and/or processing of the NVSM control module 27.

The ECC module 48 and the interface management module 50 may operate based on parameter signals from the command management module 60. The command management module 60 generates a first parameter signal 80 and a second parameter signal 82 based on commands and/or job descriptors 84 (referred to collectively as descriptors) received from the NVSM control module 27.

During a data transfer event, the NVSM control module 27 or one of the other modules of the NVSM drive 14 receives the access request signals 30. The NVSM control module 27 may include or access a first non-volatile memory 90. The first non-volatile memory 90 stores firmware 92 executed by the NVSM control module 27. In executing the firmware 92, the NVSM control module 27 generates the descriptors 84 based on the access request signals 30. The descriptors 84 are stored in a second non-volatile memory 94. The second non-volatile memory 94 may be part of the command management module 60 or separate from the command management module 60, as shown. The second non-volatile memory 94 may store the descriptors 84 and parameter information 96 for interpreting the descriptors 84 received from the NVSM control module 27 to determine parameters and generate the parameter signals 80, 82, as described below.

In generating the descriptors 84, the NVSM control module 27 may determine: a size of an allocation block of data based on the access request signals, tables relating sizes of blocks of data to other parameters, an application of use, etc. A size of an allocation block of data may be referred to as an allocation unit (AU) size or an allocation block size. An application of use may indicate, for example, a type of host, a type of NVSM drive, and speeds of the host and the NVSM drive. The NVSM control module 27 generates the descriptors 84 to indicate the allocation block sizes. The descriptors 84 may each include: the allocation block sizes; buffer register locations; NVSM addresses; NVSM channel identifiers (IDs); NVSM device identifiers (e.g., memory chip IDs); data formats; amounts of data to transfer; type of operation bits (e.g., read, program, and/or erase bits); etc.

Each of the allocation block sizes may be page based, sub-page based, or non-page based. An allocation block size is page based when the allocation block size is equal to the size of one or more pages of data. As an example a single page of data may be equal to 8 kilobytes (KB). Other example page sizes are 4 KB, 16 KB, and 32 KB. An allocation block size is sub-page based when the size of two or more allocation blocks of data is equal to the size of 1 page of data. An allocation block size is non-page based when the allocation block size is not an integer multiple of 1 page and an integer multiple of the allocation block size is not equal to the size of 1 page of data.

Allocation blocks of data may be transferred to and from channels 100 of the NVSM 28. A transfer of one or more allocation blocks of data (“blocks of data”) may be referred to as a data transfer event. Data transfer events may also occur, for example, between devices in series with and/or communicating with the channels. Example data transfer events between example devices and/or modules are shown in FIGS. 7, 14 and 15.

The command management module 60 may determine: allocation block sizes, an ECC correction power (number of bit errors per data block corrected); buffer register locations; NVSM addresses; data formats; amounts of data to transfer; redundant array of independent disks (RAID) operations; read, program, and/or erase bits; etc. based on the descriptors 84. The command management module 60 executes the descriptors 84 and/or generates the first and second parameter signals 80, 82 based on the descriptors 84.

The first parameter signal 80 may include: an ECC correction power bit; buffer register location bits; NVSM address bits; data format bits; amount of data to transfer bits; a number of blocks of data to transfer bits; redundant array of independent disks (RAID) operation bits; read, program, and/or erase bits; etc. The second parameter signal 82 may include: NVSM address bits; allocation block size bits; a number of blocks of data to transfer bits; read, program, and/or erase bits; etc.

The ECC module 48 performs error correction and encodes and decodes the DDSs and data received from the NVSM 28. The ECC module 48 transfers DDSs to and receives DDSs from the interface management module 50 based on the first parameter signal 80. The interface management module 50 accesses the NVSM 28 based on the second parameter signal 82. The interface management module 50 transmits instruction signals 102 to the NVSM 28 to control access to the NVSM 28. The NVSM 28 transmits data signals to the interface management module 50 and/or receives data signals from the interface management module 50 via the channels 100 based on and/or according to the instruction signals 102. The instruction signals 102 may include, for example, a cycle type signal CT, a timing strobe signal DQx, and a status register bit signal SR[6], examples of which are shown in FIGS. 4-6 and 8-13.

The ECC module 48 and/or other ECC modules may be connected: between the compression module 40 and the encryption module 42 to encode compressed HDSs; between the encryption module 42 and the buffer managing module 44 to encode encrypted HDSs; between the buffer managing module 44 and the DDS generating module 46; and/or between the DDS generating module 46 and the NVSM 28 as shown. The DDSs are then stored in the NVSM 28.

The ECC module 48 may use one or more ECC methods to prevent errors when writing data to and reading data from the NVSM 28. Parity bits may be generated and added to the DDSs prior to being stored in the NVSM 28 and/or may be stored separate from the DDSs in the NVSM 28.

The interface management module 50 may store the DDSs at physical block addresses (PBAs) in the NVSM 28. The PBAs of the DDSs may be stored in one or more locations and acquired by the interface management module 50 when accessing storage locations of the DDSs in the NVSM 28. For example, the PBAs may be stored in the first non-volatile memory 90 and/or in the NVSM 28. The first non-volatile memory 90 or the NVSM 28 may store a mapping table 104 of the PBAs, which may be based on an allocation block size. As an example, PBA(s) associated with an allocation block may be identified in the mapping table 104. This is different than storing the PBAs based on a size of a page of data. The allocation block size may be set based on or independent of a size of a page of data. Since the firmware 92 stores the PBAs based on allocation block size, a change in allocation block size does not require a change in firmware instructions, but rather simply an allocation block size setting adjustment. The mapping table 104 may relate logical block addresses (LBAs) to PBAs. The mapping table 104 may be accessed by any of the modules in the receive and transmit paths 22, 24.

The interface management module 50 may access DDSs in the NVSM 28 prior to forwarding the DDSs to the ECC module 48. The ECC module 48 may decode DDSs accessed from the NVSM 28 based on access command signals and/or parity information associated with the DDSs. The access command signals may be generated by the NVSM control module 27 and/or the command management module 60 and include the first parameter signal 80. The access command signals may include one or more PBAs. The access command signals may be generated by the NVSM control module 27 and based on LBAs and/or access request signals received from the host 12. The HDS generating module 52 accesses or receives the DDSs from the ECC module 48 based on data request signals received, for example, from the buffer managing module 44.

The HDS generating module 52 and/or the buffer managing module 44 separate the received DDSs into HDSs. The HDS generating module 52 generates one or more HDSs based on decrypted DDSs received from the ECC module 48. The HDS generating module 52 generates the HDSs based on the HDS identification information and/or a data request signal. The data request signal may include one or more LBAs. The decryption module 54 decrypts decoded DDSs from the ECC module 48. The keys used by the encryption module 42 may be shared, accessed and/or generated by the decryption module 54.

Although the modules of the receive and transmit paths 22, 24 are shown in a particular order, they may be rearranged in a different order. For example, the encryption module 42 may be located upstream from the compression module 40. In other words, the encryption module 42 may be connected between the NVSM drive interface 20 and the compression module 40. As another example, the decryption module 54 may be connected between the NVSM drive interface 20 and the decompression module 56.

The following FIGS. 2-11 illustrate other examples of implementations of the NVSM storage system 10.

Referring now also to FIG. 2, a portion 120 of the interface management control system 26 is shown including the ECC module 48, the interface management module 50, and the NVSM 28. The ECC module 48 includes an encoder 122 and a decoder 124. The encoder 122 encodes DDSs and forwards the encoded DDSs in the form of allocation blocks of data to the interface management module 50. The encoder 122 may combine an integer multiple of DDSs to form an allocation block of data. The decoder 124 decodes allocation blocks of data from the interface management module 50 to generate DDSs.

The interface management module 50 includes, for the example shown, a first series of FIFO registers 126 and a second series of FIFO registers 128. The first series of FIFO registers 126 are associated with program events and are used to buffer data transferred from the ECC module 48 to the NVSM 28. The second series of FIFO registers 128 are associated with read events and are used to buffer data transferred from the NVSM 28 to the ECC module 48. Although a FIFO register series is shown for each of the encoder 122 and decoder 124, the interface management module 50 may include a single series of FIFO registers, which are shared by the encoder 122 and the decoder 124. The first and second FIFO registers 126, 128 may include, for example, SRAM or other suitable memory devices.

The size of each of the FIFO registers 126, 128 may be greater than or equal to an allocation block size set by the NVSM control module 27. The size of each of the FIFO registers 126, 128 may be greater than, equal to, or less than the size of a page of data, as the allocation block size may be greater than, equal to, or less than the size of a page of data. An example of FIFO registers sized equal to a size of a page of data is shown in FIG. 7. An example of FIFO registers sized less than a size of a page of data is shown in FIG. 14.

The interface management module 50 communicates with the NVSM 28 over the channels 100 _(1-N). Each of the FIFO registers 126, 128 is associated with a respective one of the channels 100 _(1-N). The FIFO registers 126, 128 temporarily store data prior to being stored in the NVSM 28 and/or prior to being transferred to the buffer managing module 44 (shown in FIG. 1). The NVSM 28 may include buffers 130 for each of the channels 100 _(1-N). The FIFO registers 126, 128 and/or the buffers 130 may be used to balance different bandwidths (or speeds) between the encoder 122 and the NVSM 28 and/or between the decoder 124 and the NVSM 28.

The bandwidth of the ECC module 48 may be different than the bandwidth of the NVSM 28. The speeds of the encoder 122 and the decoder 124 may be faster than the speeds of each of the channels 100 _(1-N). For example, the speeds of each of the encoder 122 and the decoder 124 may be 8-16 times faster than the speed of each of the channels 100 _(1-N). Speed differences may also result due to, for example, data flow “bottlenecks” or delays in one or more of the channels 100 _(1-N), which may be due to operations of the interface management module 50 and NVSM 28. The FIFO registers 126, 128 and the buffers 130 aid in balancing out the speed differences. The speed of the encoder 122 may be set to maintain operation of the channels 100 _(1-N) at peak operating speeds. The speed of the decoder 124 may be set to prevent filling of the second set of FIFO registers 128 and maintain output of the channels 100 _(1-N) at the peak operating speeds.

In the following FIGS. 3-6 and 8-13, multiple timing diagrams are shown. The timing diagrams include multiple instruction signals, which may be transmitted from the interface management module 50 to the NVSM 28 of FIG. 1. The instruction signals 102 include cycle type signals CT, timing strobe signals DQx, and status register bit signals SR[6]. The cycle type signals CT identify the type of instruction being provided in the timing strobe signals DQx. The timing strobe signals DQx may include, for example, command instructions CMD, NVSM address instructions ADDR, read instructions DOUT, program instructions DIN, which are identified by the cycle type signals CT. The timing strobe signals DQx identify the commands, the addresses, and the data being read or programmed. Examples of commands are a start of read command (e.g., 00 h, 06 h), an end of read command (e.g., 30 h, 32 h, EOh), a start of program command (e.g., 80 h), and an end of program command (e.g., 10 h). Examples of addresses are a column address (e.g., C1, C2) and a row address (e.g., R1, R2, R3).

The status register signals SR[6] indicate wait times between instruction sets of the cycle type signals CT and the timing strobe signals DQx. An instruction set may be an initiating (or triggering) instruction set, a read instruction set, or a program instruction set. The triggering instruction sets are used to signal the NVSM 28 that; a read operation or a program operation is to be performed; the amount of data and/or the number of allocation blocks being transferred; the addresses of the allocation blocks; etc. The read instruction sets refer to when data is transferred (or loaded) from the NVSM 28 to the interface management module 50 or the ECC module 48. The program instruction sets refer to when data is transferred from the interface management module 50 or the ECC module 48 to the NVSM 28.

The wait periods may include a trigger to prepare period tWB, a read preparing period tR, a ready to read period tRR, a trigger to load period tADL, a program preparing period tPROG, a plane busy period tPBSY, a change column setup period tCCS, etc. The NVSM 28 prepares for data transfer events during the read preparing period tR and the program preparing period tPROG. Each data transfer event has a single read preparing period or a single program preparing period.

Also, in the following FIGS. 3-6 and 8-13, multiple instruction sets are shown. The instruction sets are provided as part of the cycle type and timing strobe signals CT, DQx. Each of the instruction sets includes groups of instructions separated by one or more of the above-described wait periods. The instructions are shown as hexagonally-shaped blocks. Each instruction set may include any number of instructions.

Also, in the following FIGS. 3-6 and 8-13, multiple descriptors are identified. Arrows of the descriptors do not necessarily refer to the timing of the descriptors. The arrows of the descriptors are provided to identify the instructions that are generated based on each one of the descriptors. For each one of the descriptors, one or more sets of instructions are generated. For example, in FIG. 5 multiple page descriptors₁₋₃ are shown with respective arrows and corresponding instructions. The page descriptors₁₋₃ may be generated by the NVSM control module 27 and transmitted to the command management module 60 prior to the instructions shown in FIG. 5 being generated.

The descriptors of FIGS. 3-6 and 8-13 may be page descriptors or allocation block descriptors. A page descriptor refers to a descriptor used to trigger and/or transfer one or more pages of data. An allocation block descriptor refers to a descriptor used to trigger and/or transfer one or more allocation blocks of data. The page descriptors and the allocation block descriptors may be trigger descriptors, read descriptors, or program descriptors. The trigger descriptors are used to initialize a data transfer event (read or program event). As an example, the trigger descriptors may identify a command type (read or program), target addresses within the NVSM 28 and/or buffer managing module 44, and how much data is to be transferred (e.g., number of pages and/or number of allocation blocks).

The read descriptors are used to read data from the NVSM 28. The program descriptors are used to program data to the NVSM 28. As an example, the read descriptors and the program descriptors may identify how much data is to be transferred and the locations of the data within a page of data. A descriptor may be both a trigger descriptor and a read descriptor. See, for example, the first descriptor (AU descriptor₁) of FIG. 8. A descriptor may alternatively be both a trigger descriptor and a program descriptor. See, for example, the first descriptor (AU descriptor₁) of FIG. 11.

Referring now to FIGS. 1 and 3, a timing diagram illustrating a single page read event for a page based transfer is shown. The timing diagram includes instruction signals CT (145), DQx (146) and SR[6] (147) that are generated based on a single page descriptor with arrow 148. The instruction signals 145-147 are examples of the instruction signals 102. As illustrated, each of the cycle type and timing strobe signals 145, 146 include two instruction sets 150, 152. The first instruction sets 150 are triggering instruction sets. The second instruction sets 152 are read instruction sets. Each of the instruction sets 150, 152 includes instructions (shown as hexagonally-shaped blocks).

The page descriptor may be generated by the NVSM control module 27. The command management module 60 generates the first and second parameter signals 80, 82 based on the page descriptor. The interface management module 50 generates the instruction signals 145, 146 and 147 based on the second parameter signal 82. The NVSM 28 prepares for a data transfer event based on the first instruction sets of the instruction signals during the read preparing period tR.

The NVSM 28 transfers a page of data via one of the channels 100 to the interface management module 50 based on the instruction signals 145, 146 and 147 subsequent to the read preparing period tR. The amount of data (or size of the block of data) transferred for this read event may be equal to the size of 1 page of data. As an alternative, the size of the block of data transferred may be less than 1 page of data. The amount of data transferred may be equal to a size of an allocation block of data. The size of the allocation block may be set as described above. An allocation block descriptor may be used as an alternative to the page descriptor 148 when allocation blocks of data are transferred. An allocation block descriptor refers to a descriptor that is used to trigger and/or transfer one or more allocation blocks of data.

Referring now to FIGS. 1 and 4, a timing diagram illustrating a single page program event for a page based transfer is shown. The timing diagram includes instruction signals CT (155), DQx (156) and SR[6] (157) that are generated based on a single page descriptor with arrow 160. The instruction signals 155-157 are examples of the instruction signals 102. As illustrated, the signals 155 and 156 each include two instruction sets 162, 164. The first instruction sets 162 are triggering instruction sets. The second instruction sets 164 are program instruction sets.

The page descriptor of FIG. 4 may be generated by the NVSM control module 27. The page descriptor is generated to both initiate (or trigger) the transfer of data and perform the transfer of the data. The command management module 60 generates the first and second parameter signals 80, 82 based on the page descriptor 160. The NVSM 28 generates the instruction signals 155-157 based on the second parameter signal 82. The NVSM 28 prepares for a data transfer event based on the first instruction sets 162 during a trigger-to-load period tADL.

The ECC module 48 transfers a page of data to the interface management module 50. The page of data may be stored in a FIFO register of the interface management module 50. The interface management module 50 transfers the page of data to the NVSM 28 via one of the channels 100. The data is transferred to the channel subsequent to the trigger-to-load period tADL and prior to a program preparing period tPROG.

The amount of data (or size of the block of data) transferred for this program event may be equal to the size of 1 page of data, as described or alternatively may be less than 1 page of data. The amount of data transferred may be equal to a size of an allocation block. The size of the allocation block of data may be set as described above. An allocation block descriptor may be used as an alternative to the page descriptor when allocation blocks of data are transferred.

Referring now to FIGS. 1 and 5, a timing diagram illustrating a multi-page (or multi-plane) read event using multiple page descriptors is shown. The timing diagram includes instruction signals CT (165), DQx (166) and SR[6] (167) that are generated based on multiple page descriptors Page Descriptor₁₋₃ with arrows 170, 172, 174. As illustrated, each of the signals 165 and 166 include six instruction sets 176, 178, 180, 182, 184, 186. The instruction signals 165-167 are examples of the instruction signals 102. The first and second instruction sets 176, 178 are triggering instruction sets for the multi-page read event. The third and fifth instruction sets 180, 184 are triggering instructions for each page. The fourth and sixth instruction sets 182, 186 are read instruction sets.

The six instruction sets 176-186, as shown, are used to transfer 2 pages of data. Additional instructions sets may be added for additional pages. In this example, the number of triggering instructions sets T per signal is equal to twice the number of pages P transferred (or T=2*P). The number of read instruction sets R per signal is equal to the number of pages P transferred (or R=P). Also, the number of page descriptors D is equal to the number of pages plus one (or D=P+1).

The page descriptors Page Descriptor₁₋₃ may be generated by the NVSM control module 27. The command management module 60 generates the first and second parameter signals 80, 82 based on the page descriptors Page Descriptor₁₋₃. The NVSM 28 generates the instruction signals 165-167 based on the second parameter signal 82. The NVSM 28 prepares for a data transfer event for transferring the pages of data based on the first and second instruction sets 176, 178.

The NVSM 28 then prepares for and transfers each of the pages of data via one or more of the channels 100 to the interface management module 50 based on the instruction signals (i.e. the instruction sets 180-186) subsequent to a read prepping period tR. The amount of data (or size of the block of data) transferred for each pair of read instruction sets 182, 186 (1 read instruction set for the CT signal and 1 read instruction set for the DQx signal) may be equal to the size of 1 page of data. As an alternative, the size of the block of data transferred may be less than 1 page of data. The amount of data transferred may be equal to a size of an allocation block of data. The size of the allocation block of data may be set as described above. Allocation block descriptors may be used as an alternative to page descriptors Page Descriptor₁₋₃ when allocation blocks of data are transferred. An example of this is shown in FIG. 10.

Referring now to FIGS. 1 and 6, a timing diagram illustrating a multi-page program event using multiple page descriptors is shown. The timing diagram includes instruction signals CT (187), DQx (188) and SR[6] (189) that are generated based on multiple page descriptors Page Descriptor₁₋₂ with arrows 190, 192. The instruction signals 187-189 are examples of the instruction signals 102. As illustrated, the signals 187 and 188 each include four instruction sets 194, 196, 198, 200. The first and third instruction sets 194, 198 are triggering instruction sets for the multi-page read event. The second and fourth instruction sets 196, 200 are program instruction sets.

The four instruction sets 194-200, as shown, are used to transfer 2 pages of data. Additional instructions sets may be added for additional pages. In this example, the number of triggering instructions sets T per signal is equal to the number of pages P transferred (or T=P). The number of program instruction sets G per signal is equal to the number of pages P transferred (or G=P). Also, the number of page descriptors D is equal to the number of pages transferred (or D=P).

The page descriptors Page Descriptor₁₋₂ may be generated by the NVSM control module 27. The page descriptors Page Descriptor₁₋₂ may be generated by the NVSM control module 27. The command management module 60 generates first and second parameter signals 80, 82 based on the page descriptors Page Descriptor₁₋₂. The NVSM 28 generates the instruction signals 187-189 based on the second parameter signal 82. The NVSM 28 prepares for data transfer events based on the first and third instruction sets 194, 198 during respective trigger-to-load periods tADL1, tADL2.

The ECC module 48 transfers the pages of data to the interface management module 50. The pages of data may be stored in FIFO registers of the interface management module 50. The interface management module 50 transfers the pages of data to the NVSM 28 via one of the channels 100. The pages of data is transferred to the channel subsequent to the trigger-to-load periods tADL1, tADL2 and prior to a program preparing period tPROG.

The amount of data (or size of the blocks of data) transferred for each of the program instructions 196, 200 may be equal to the size of 1 page of data, as described or alternatively may be less than 1 page of data. The amount of data transferred may be equal to a size of an allocation block of data. The size of the allocation block may be set as described above. Allocation block descriptors may be used as an alternative to the page descriptors Page Descriptor₁₋₂ when allocation blocks of data are transferred. An example of this is shown in FIG. 13.

In the above FIGS. 5 and 6, as there is a single read preparing period tR and a signal program period tPROG, wait time is minimized for multi-page transfer events.

In FIG. 7, a portion 210 of an interface management control system is shown illustrating multi-page program events with page-sized transfers. The portion 210 may be incorporated into the interface management control system 26 of FIG. 1. Each transfer may fill one of the FIFO registers 126 of the interface management module 50. Each page of data transferred may have two associated page descriptors (not shown), as described above with respect to FIG. 6.

Each of the FIFO registers 126 is connected to a respective one of Channels₀₋₇ of the NVSM 28. Channels₀₋₇ may be included in the channels 100 of FIG. 1. Although the FIFO registers 126 may each be sized to store more than 1 page of data, the FIFO registers 126 are each shown as being able to store 1 page of data. If a multi-page (M-page) transfer is performed (as described above), the FIFO registers 126 do not need to be sized to store M pages of data, as one or more page descriptors are used per page of data transferred. Sizing the FIFO registers 126 to store a single page of data rather than two or more pages of data reduces memory allocated for the FIFO registers 126 and decreases data transfer times. If only a single descriptor was used to transfer the M pages of data, each of the FIFO registers 126 would need to be sized to equal the amount of data in a page of data, because each descriptor is associated with a single channel and/or a single FIFO register.

In a multi-page transfer event, data that is provided to the interface management module 50 is spread across multiple channels page-by-page. Pages of data Data₁₋₁₆ are shown. A single page is transferred to each of the Channels₀₋₂ prior to sending a second page to any of the Channels₀₋₂. The pages of data are transferred from the FIFO registers 126 to the Channels₀₋₇ based on speeds of the Channels₀₋₂ and/or devices internal to the NVSM 28. As the pages of data are transferred to each of the FIFO registers 126, probability of a data bottleneck at any one of the FIFO registers 126 is reduced. For example, if transfer speed of a first channel (e.g., Channel₀) is slow, a bottleneck at a corresponding first FIFO register FIFO₁ may not occur, as pages of data are loaded into the other FIFO registers FIFO₂₋₈ prior to loading another page of data into the first FIFO register FIFO₁.

Referring now to FIGS. 1 and 8, a timing diagram illustrating a read event with the same number of descriptors as allocation blocks transferred is shown. The timing diagram includes instruction signals CT (217), DQx (218) and SR[6] (219) that are generated based on multiple allocation block descriptors AU Descriptor₁₋₂ with arrows 220, 222. The instruction signals 217-219 are examples of the instruction signals 102. As illustrated, the signals 217 and 218 each include three instruction sets 224, 226, 228. The first instruction sets 224 are triggering instruction sets. The second instruction sets 226 are first read instruction sets. The third instruction sets 228 are second read instruction sets.

Each of the read instruction sets 226, 228 is associated with an allocation block of data. The first descriptor AU Descriptor₁ is associated with the first and second instruction sets 226, 228. A second descriptor AU Descriptor₂ is associated with the third instruction sets 228.

The allocation block descriptors AU Descriptor₁₋₂ may be generated by the NVSM control module 27. The command management module 60 generates the first and second parameter signals 80, 82 based on the allocation block descriptors AU Descriptor₁₋₂. The interface management module 50 generates the instruction signals 217-219 based on the second parameter signal 82. The NVSM 28 prepares for a data transfer event based on the first instruction sets 224 during a read preparing period tR.

The NVSM 28 transfers the allocation blocks of data via one of the channels 100 to the interface management module 50 based on the instruction signals 217-219 subsequent to the read preparing period tR. The allocation blocks of data may be spread block-by-block to different, adjacent and/or sequential FIFO registers of the interface management module 50. The amount of data (or size of the allocation blocks of data) transferred for this read event may be, for example, less than or equal to the size of 1 page of data. The size of the allocation blocks of data may be set as described above.

Referring now to FIGS. 1 and 9, a timing diagram illustrating a read event with more descriptors than allocation blocks transferred is shown. The timing diagram includes instruction signals CT (227), DQx (228) and SR[6] (229) that are generated based on multiple allocation block descriptors AU Descriptors₁₋₃ with arrows 230, 232, 234. The instruction signals 227-229 are examples of the instruction signals 102. The number of allocation block descriptors AUD is equal to the number of allocation blocks AB transferred plus one (or AUD=AB+1). As illustrated, each of the signals 227 and 228 includes three instruction sets 236, 238, 240. The first instruction sets 236 are triggering instruction sets. The second instruction sets 238 are first read instruction sets. The third instruction sets 240 are second read instruction sets.

Each pair of read instruction sets 238, 240 (1 read instruction set in the CT signal and 1 read instruction set in the DQx signal) is associated with an allocation block of data. The first descriptor AU Descriptors₁ is associated with the first instruction sets 236. The second descriptor AU Descriptors₂ is associated with the second instruction sets 238. The third descriptor AU Descriptors₃ is associated with the third instruction sets 240.

The allocation block descriptors AU Descriptors₁₋₃ may be generated by the NVSM control module 27. The command management module 60 generates the first and second parameter signals 80, 82 based on the allocation block descriptors AU Descriptors₁₋₃. The interface management module 50 generates the instruction signals 227-229 based on the second parameter signal 82. The NVSM 28 prepares for a data transfer event based on the first instruction sets 236 during a read preparing period tR.

The NVSM 28 transfers the allocation blocks of data via one of the channels 100 to the interface management module 50 based on the instruction signals 227-229 subsequent to the read preparing period tR. The amount of data (or size of the allocation blocks of data) transferred for this read event may be, for example, less than or equal to the size of 1 page of data. The size of the allocation blocks of data may be set as described above.

The implementation of FIG. 8 uses fewer descriptors than the implementation of FIG. 9. The use of fewer descriptors may decrease the number of signals generated and transferred between the modules of the interface management control system 26. The use of fewer descriptors may also reduce mapping table size and operations of the NVSM control module 27. The use of more descriptors by the implementation of FIG. 8 can increase firmware design flexibility by providing increased data transfer control of instruction sets and management of smaller sized allocation blocks.

Referring now to FIGS. 1 and 10, a timing diagram illustrating a multi-allocation block read event with multiple instruction sets is shown. The implementation of FIG. 10 is similar to the implementation of FIG. 5, except allocation block descriptors are generated to transfer allocation blocks of data instead of page descriptors being generated to transfer pages of data. The timing diagram includes instruction signals CT (247), DQx (248) and SR[6] (249) that are generated based on multiple allocation block descriptors AU Descriptors₁₋₃ with arrows 250, 252, 254. The instruction signals 247-249 are examples of the instruction signals 102.

As illustrated, the signals 247 and 248 each include six instruction sets 256, 258, 260, 262, 264, 266. The first and second instruction sets 256, 258 are triggering instruction sets for the multi-page read event. The third and fifth instruction sets 260, 264 are triggering instructions for each page. The fourth and sixth instruction sets 262, 266 are read instruction sets. The six instruction sets 256-266, as shown, are used to transfer 2 pages of data. Additional instructions sets may be added for additional pages. In this example, the number of triggering instructions sets T per signal is equal to twice the number of pages P transferred (or T=2*P). The number of read instruction sets R per signal is equal to the number of pages P transferred (or R=P). Also, the number of page descriptors D is equal to the number of pages minus one (or D=P−1).

The allocation block descriptors AU Descriptors₁₋₃ may be generated by the NVSM control module 27. The command management module 60 generates first and second parameter signals 80, 82 based on the allocation block descriptors AU Descriptors₁₋₃. The NVSM 28 generates the instruction signals 247-249 based on the second parameter signal 82. The NVSM 28 prepares for a data transfer event for transferring the allocation blocks of data based on the first and second instruction sets 256, 258.

The NVSM 28 then prepares for and transfers each of the allocation blocks of data via one or more of the channels to the interface management module 50 based on the instruction signals 247-249 (i.e. the instructions sets 260, 264) subsequent to a read preparing period tR. The amount of data (or allocation block size) transferred for each pair of read instruction sets 262, 266 (1 read instruction set for the CT signal and 1 read instruction set for the DQx signal) may be less than or equal to the size of 1 page of data.

Referring now to FIGS. 1 and 11, a timing diagram illustrating a program event with the same number of descriptors as allocation blocks transferred is shown. The timing diagram includes instruction signals CT (267), DQx (268) and SR[6] (269) that are generated based on multiple allocation block descriptors AU Descriptors₁₋₂ with arrows 270, 272. The instruction signals 267-269 are examples of the instruction signals 102. As illustrated, the signals 267 and 268 each include three instruction sets 274, 276, 278. The first instruction sets 274 are triggering instruction sets. The second instruction sets 276 are first program instruction sets. The third instruction sets 278 are second program instruction sets.

The allocation block descriptors AU Descriptors₁₋₂ may be generated by the NVSM control module 27. The command management module 60 generates first and second parameter signals 80, 82 based on the allocation block descriptors AU Descriptors₁₋₂. The NVSM 28 generates the instruction signals 267-269 based on the second parameter signal 82. The NVSM 28 prepares for a data transfer event based on the first instruction sets 274 during a trigger-to-load period tADL.

The ECC module 48 transfers the allocation blocks of data to the interface management module 50. The allocation blocks of data may be stored in a FIFO register of the interface management module 50. The interface management module 50 transfers the allocation blocks of data to the NVSM 28 via one of the channels 100. The data is transferred to the channel subsequent to the trigger-to-load period tADL and prior to a program preparing period tPROG. The amount of data (the combined size of the allocation blocks of data) transferred for this program event may be less than or equal to the size of 1 page of data.

Referring now to FIGS. 1 and 12, a timing diagram illustrating a program event with more descriptors than allocation blocks transferred is shown. The timing diagram includes instruction signals CT (277), DQx (278) and SR[6] (279) that are generated based on multiple allocation block descriptors AU Descriptors₁₋₃ with arrows 280, 282, 284. The instruction signals 277-279 are examples of the instruction signals 102. The number of allocation block descriptors AUD is equal to the number of allocation blocks AB transferred plus one (or AUD=AB+1). As illustrated, the 277 and 278 signals each include three instruction sets 286, 288, 290. The first instruction sets 286 are triggering instruction sets. The second instruction sets 288 are first program instruction sets. The third instruction sets 290 are second program instruction sets.

The allocation block descriptors AU Descriptors₁₋₃ may be generated by the NVSM control module 27. The command management module 60 generates the first and second parameter signals 80, 82 based on the allocation block descriptors AU Descriptors₁₋₂. The NVSM 28 generates the instruction signals 277-279 based on the second parameter signal 82. The NVSM 28 prepares for a data transfer event based on the first instruction sets 286 during a trigger-to-load period tADL.

The ECC module 48 transfers the allocation blocks of data to the interface management module 50. The allocation blocks of data may be stored in a FIFO register of the interface management module 50. The interface management module 50 transfers the allocation blocks of data to the NVSM 28 via one of the channels 100. The data is transferred to the channel subsequent to the trigger-to-load period tADL and prior to a program preparing period tPROG. The amount of data (the combined size of the allocation blocks of data) transferred for this program event may be less than or equal to the size of 1 page of data.

Referring now to FIGS. 1 and 13, a timing diagram illustrating a multi-allocation block read event with multiple instruction sets is shown. The implementation of FIG. 13 is similar to the implementation of FIG. 6, except allocation block descriptors are generated to transfer allocation blocks of data instead of page descriptors being generated to transfer pages of data. In addition, two page descriptors are generated per allocation block of data transferred instead of a single page descriptor being generated per page of data transferred.

The timing diagram of FIG. 13 includes instruction signals CT (297), DQx (298) and SR[6] (299) that are generated based on multiple allocation block descriptors AU Descriptors₁₋₄ with arrows 300, 302, 304, 306. The instruction signals 297-299 are examples of the instruction signals 102. As illustrated, the signals 297 and 298 each include six instruction sets 308, 310, 312, 314, 316, 318. The first and fourth instruction sets 308, 314 are triggering instruction sets for the multi-allocation block read event. The second and fifth instruction sets 310, 316 are program instruction sets for first and third allocation blocks of data. The third and sixth instruction sets 312, 318 are program instruction sets for transferring second and fourth allocation blocks of data. Additional trigger and program instructions sets may be added for additional allocation blocks of data.

In this example, the number of triggering instructions sets T per signal is equal to twice the number of allocation blocks of data AB transferred (or T=2*AB). The number of program instruction sets G per signal is equal to the number of allocation blocks of data transferred (or G=AB). The number of allocation blocks per trigger instruction set may be increased by the NVSM control module 27.

The allocation block descriptors AU Descriptors₁₋₄ may be generated by the NVSM control module 27. The command management module 60 generates the first and second parameter signals 80, 82 based on the allocation block descriptors AU Descriptors₁₋₄. The NVSM 28 generates the instruction signals 297-299 based on the second parameter signal 82. The NVSM 28 prepares for a data transfer event based on the first instruction sets 308, 314 during trigger-to-load periods tADL1, tADL2.

The ECC module 48 transfers the allocation blocks of data to the interface management module 50. The first and second allocation blocks of data may be stored in a first FIFO register of the interface management module 50. The third and fourth allocation blocks of data may be stored in a second FIFO register of the interface management module 50. The interface management module 50 may transfer the allocation blocks of data to the NVSM 28 via two of the channels 100. The allocation blocks of data are transferred to the channels subsequent to the trigger-to-load periods tADL1, tADL2 and prior to a program preparing period tPROG. As an alternative, the first, second, third, and fourth blocks of data may be transferred to one of the first and second FIFO registers and transferred to the NVSM 28 via one of the channels 100.

The amount of data (or size of the allocation blocks of data) transferred for each pair of the program instruction sets (the first and second program instruction sets 310, 312 or the third and fourth program instruction sets 316, 318) may be less than or equal to the size of 1 page of data. In the example shown, if 1 page of data is transferred for each pair of trigger instruction sets (1 trigger instruction set for the CT signal and 1 trigger instruction set for the DQx signal), then the size of two allocation blocks is equal to the size of a page of data. The number of allocation blocks per transfer of a page of data may be increased by reducing the allocation block size.

In FIG. 14, a portion 330 of an interface management control system is shown illustrating an allocation block based program events with allocation block sized transfers. This portion 330 may be incorporated into the interface management control system 26 of FIG. 1. Each allocation block of data transferred may fill one of FIFO registers 126′ of the interface management module 50. Each allocation block of data transferred may have, for example, two or three associated allocation block descriptors (not shown), as described above with respect to FIGS. 11 and 12.

Each of the FIFO registers 126′ is connected to one of Channels₀₋₇ of the NVSM 28. Although the FIFO registers 126′ may each be sized to store more than 1 allocation block of data, the FIFO registers 126′ are each shown as being able to store 1 allocation block of data.

The size of each of the FIFO registers 126′ may be based on the size of the allocation blocks of data and may be independent of a size of a page of data. Any number of allocation blocks may be equal to the size of one page of data. Reducing the sizes of the allocation blocks of data and the FIFO registers 126′ can further increases data transfer speeds, increase parallel data transfer efficiency, and prevent data bottlenecks.

In a multi-allocation block transfer event, data that is provided to the interface management module 50 is spread across multiple channels block-by-block. Allocation blocks of data Data₁₋₃₂ are shown. A single allocation block of data is transferred to each of the channels prior to sending a second allocation block to any of the channels. The allocation blocks of data are transferred from the FIFO registers 126′ to the channels based on speeds of the channels and/or devices internal to the NVSM 28. As the allocation blocks of data are transferred to each of the FIFO registers 126′, probability of a data bottleneck at any one of the FIFO registers 126 is reduced.

Referring now to FIGS. 1 and 15, a portion 340 of an interface management control system is shown. The portion 340 may be incorporated into the interface management control system 26 of FIG. 1, replace the portion 120 of FIG. 2, and includes an ECC module 48′, an interface management module 50′ and the NVSM 28. Unlike the implementation of FIG. 2, the ECC module 48′ includes multiple encoders 342 and multiple decoders 344 and the interface management module 50′ does not include FIFO registers. Each of the encoders 342 may transfer data at approximately the same speed as the channels 100 of the NVSM 28.

During a program event, the DDS generating module 46 may spread allocation blocks of data to the encoders 342 similar to the spreading of allocation blocks of data to FIFO registers as described with respect to the implementations of, for example, FIGS. 2 and 8-14. The implementation of FIG. 15 further decreases the amount of memory used to transfer data to and from the NVSM 28 by not incorporating FIFO registers in the interface management module 50′. As FIFO registers are not incorporated, this implementation can support any page size or allocation block size. This increases development flexibility of the firmware 92. This implementation may also increase parallel data transfer efficiency.

Use of FIFO registers with sizes less than the size of a page and/or the elimination of FIFO registers, as described in FIGS. 14 and 15, minimizes hardware/memory requirements.

The NVSM storage system 10 and/or the NVSM drive 14 may be operated using numerous methods, an example allocation block based method is provided by the method of FIG. 16. In FIG. 16, a method of operating a NVSM storage system and a NVSM drive is shown. Although the following tasks are primarily described with respect to the implementations of FIGS. 1-15, the tasks may be easily modified to apply to other implementations of the present disclosure. The tasks may be iteratively performed. The method may begin at 350.

At 352, the NVSM drive interface 20 receives access request signals from the host interface 18 requesting that read, program, and/or erase events be performed.

At 354, the NVSM control module 27 generates page and/or allocation block descriptors based on the access request signals. The page and/or allocation block descriptors may be generated to perform one or more data transfer events. Each of the data transfer events may be a read event or a program event and include only one read preparing period or one program preparing period. The number of descriptors generated per data transfer event, page of data transferred, and/or allocation block of data transferred may be determined by the NVSM control module 27.

Each of the data transfer events includes two or more descriptors. The number of pages of data and/or the number of allocation blocks of data per transfer event may also be determined by the NVSM control module 27 and indicated in the generated descriptors. One or more pages of data and/or one or more allocation blocks of data may be transferred per data transfer event. Page sizes may be predetermined and fixed or may be set by the NVSM control module 27.

At 356, the command management module 60 generates the first parameter signal 80 and the second parameter signal 82 as described above based on the page and/or allocation block descriptors generated at 354.

At 358, an ECC module (e.g., one of the ECC modules 48, 48′) and an interface management module (e.g., one of the interface management modules 50 50′) determine whether a read event or a program event is to be performed based on the first parameter signal 80 and the second parameters signal 82. Task 360 is performed when a read event is performed. Task 370 is performed when a program event is performed.

At 360, the interface management module generates the instruction signals 102 to instruct the NVSM 28 to transfer blocks of data from the NVSM 28 to the interface management module via the channels 100. The instruction signals 102 are generated based on the second parameter signal 82.

At 362, the NVSM 28 prepares for and transfers the pages of data and/or the allocation blocks of data to one or more of the channels 100 based on instruction sets of the instruction signals. The instruction sets may be as shown in, for example, FIGS. 3, 5, 8, 9 and/or 10. The pages of data and/or the allocation blocks of data may be received by FIFO registers of the interface management module.

At 364, the pages of data and/or the allocation blocks of data are transferred from the interface management module to the ECC module based on the parameter signals 80, 82. The pages of data and/or the allocation blocks of data may be transferred to one or more decoders of the ECC module, as shown in FIGS. 2, 7, 14 and 15.

At 366, the pages of data and/or the allocation blocks of data are transferred to the NVSM drive interface 20 via, for example, the HDS generating module 52, the buffer managing module 44, the decryption module 54 and the decompression module 56. The host 12 may receive the pages of data and/or the allocation blocks of data from the NVSM drive interface 20. Subsequent to performing task 366, the method may return to task 352 or end at 380, as shown.

At 370, the pages of data and/or the allocation blocks of data are received by the NVSM drive interface 20. At 371, the pages of data and/or the allocation blocks of data are forwarded to the ECC module via, for example, the compression module 40, the encryption module 42, the buffer managing module 44 and the DDS generating module 46.

At 372, the ECC module may transfer the pages of data and/or the allocation blocks of data to the interface management module based on the first parameter signal 80. The pages of data and/or the allocation blocks of data may be transferred from an encoder of the ECC module and spread to one or more FIFO registers of the interface management module, as shown in FIG. 2, 7 or 14. As an alternative, the pages of data and/or the allocation blocks of data may be transferred from multiple encoders of the ECC module to the interface management module, as shown in FIG. 15.

At 374, the interface management module generates instruction signals 102 to transfer the pages of data and/or the allocation blocks of data to the NVSM 28 based on the second parameter signal 82. The instruction signals 102 may include instruction sets. The instruction sets may be as shown in, for example, FIGS. 4, 6, 11, 12 and/or 13.

At 376, the NVSM 28 receives the pages of data and/or the allocation blocks of data via the channels 100. Subsequent to performing task 376, the method may return to task 352 or end at 380, as shown.

The above-described tasks are meant to be illustrative examples; the tasks may be performed sequentially, synchronously, simultaneously, continuously, during overlapping time periods or in a different order depending upon the application. For example, task 374 may be performed while task 376 is performed.

The implementations described herein use multiple descriptors (as defined above) per page and/or multiple descriptors per allocation block transferred to and/or from NVSM. By generating and using multiple descriptors, firmware flexibility is increased over using only a single descriptor per transfer. Performing data transfers based on a selected allocation block size allows read and program events to be performed independent of page sizes and allows a NVSM drive to accommodate any page size of a NVSM. Allocation blocks that are smaller than the size of a page are easier for firmware of a NVSM control module to handle, easier to encode and decode, and are easier for a host to handle. Reading allocation blocks from a NVSM as opposed to reading pages of data reduces read latency.

Also, allocation block based transfers allow for FIFO sizes of an interface management module of a NVSM drive to be independent of page sizes. Also, by spreading allocation blocks of data over multiple channels of a NVSM per transfer event improves transfer efficiency. The data may be spread to multiple channels without waiting for an additional block of data to be loaded into a FIFO of a channel, which has already received a block of data. This further decreases transfer latencies.

The broad teachings of the disclosure can be implemented in a variety of forms. Therefore, while this disclosure includes particular examples, the true scope of the disclosure should not be so limited since other modifications will become apparent upon a study of the drawings, the specification, and the following claims. 

What is claimed is:
 1. A system comprising: a non-volatile semiconductor memory configured to store a first block of data and a second block of data, wherein the first block of data or the second block of data is non-page based such that a size of the first block of data or a size of the second block of data is not an integer multiple of a page of data; an interface module configured to (i) transfer the first block of data during a first data transfer event, and (ii) transfer the second block of data during a second data transfer event; and a control module configured to, based on a plurality of descriptors, control the first data transfer event and the second data transfer event such that the interface module transfers the first block of data between the interface module and the non-volatile semiconductor memory while transferring the second block of data between the interface module and the non-volatile semiconductor memory, wherein the plurality of descriptors comprise a first descriptor and a second descriptor, wherein the first descriptor includes a first set of instructions for transferring the first block of data, and the second descriptor includes a second set of instructions for transferring the second block of data.
 2. The system of claim 1, wherein each of the first block of data and the second block of data is smaller than a page of data.
 3. The system of claim 1, further comprising a command module configured to generate a parameter signal based on the plurality of descriptors, wherein the interface module is configured to: based on the parameter signal, generate a first instruction signal and a second instruction signal; transmit the first instruction signal to the non-volatile semiconductor memory to have the non-volatile semiconductor memory perform the first data transfer event according to the first descriptor; and transmit the second instruction signal to the non-volatile semiconductor memory to have the non-volatile semiconductor memory perform the second data transfer event according to the second descriptor.
 4. The system of claim 1, wherein the control module is configured to, based on an access request signal from a host or a parameter, determine (i) a size of the first block of data, and (ii) a size of the second block of data.
 5. The system of claim 4, wherein: the parameter indicates a type of the host, a type of a storage drive, a speed of the host or a speed of the storage drive; and the storage drive comprises the non-volatile semiconductor memory.
 6. The system of claim 1, wherein: the control module is configured to, based on the first set of instructions and a third set of instructions, control transfer of the first block of data between the interface module and the non-volatile semiconductor memory; and each of the first set of instructions and the third set of instructions includes an address of the first block of data.
 7. The system of claim 6, wherein: the first descriptor indicates (i) an amount of data to be transferred during the first data transfer event, or (ii) whether the first data transfer event is a read event or a program event; and the second descriptor indicates (i) an amount of data to be transferred during the second data transfer event, or (ii) whether the second data transfer event is a read event or a program event.
 8. The system of claim 1, further comprising a plurality of buffers connected to respective channels of the non-volatile semiconductor memory, wherein: the plurality of buffers comprise a first buffer and a second buffer; and the interface module is configured to receive the first block of data at the first buffer while receiving the second block of data at the second buffer.
 9. The system of claim 1, wherein: the first data transfer event includes transferring a page of data including the first block of data and a third block of data; and the control module is configured to, based on a third descriptor, control transfer of the third block of data during the first data transfer event.
 10. The system of claim 1, wherein: the control module is configured to, based on a second plurality of descriptors, control transfer of the first block of data; the second plurality of descriptors include the first descriptor; and a number of the second plurality of descriptors is equal to a number of blocks of data transferred during the first data transfer event plus one.
 11. The system of claim 1, further comprising: a plurality of buffers connected respectively to a plurality of channels of the non-volatile semiconductor memory, wherein the interface module includes the plurality of buffers; and a third module configured to (i) receive a plurality of blocks of data, and (ii) concurrently transfer the plurality of blocks of data respectively to the plurality of buffers, wherein the plurality of blocks of data include the first block of data and the second block of data.
 12. The system of claim 1, wherein: the control module is configured to, based on a second plurality of descriptors, control transfer of the first block of data, wherein the second plurality of descriptors includes the first descriptor and does not include the second descriptor; and a number of the second plurality of descriptors is twice a number of blocks of data transferred during the first data transfer event.
 13. The system of claim 1, wherein: the first descriptor comprises the first set of instructions and a third set of instructions; and the second descriptor comprises the second set of instructions and a fourth set of instructions.
 14. The system of claim 13, wherein: the first descriptor indicates transfer of the first block of data and a third block of data; the second descriptor indicates transfer of the second block of data; the plurality of descriptors comprise a third descriptor; the third descriptor (i) indicates transfer of the third block of data, and (ii) comprises a fifth set of instructions and a sixth set of instructions; the first descriptor triggers data transfer events corresponding to the third descriptor; and the third descriptor is transmitted to the interface module subsequent to the first descriptor.
 15. The system of claim 1, wherein: the first set of instructions indicates the size of the first block of data; and the second set of instructions indicates the size of the second block of data.
 16. A solid-state memory drive comprising: the system of claim 1; and a buffer managing module configured to receive first host data sectors from a host, wherein the solid-state memory drive is separate from and connected to the host, generate first drive data sectors based on the first host data sectors, receive second drive data sectors, generate second host data sectors based on the second drive data sectors, and transmit the second host data sectors to the host, wherein the interface module is configured to (i) transmit the first drive data sectors to the non-volatile semiconductor memory, and (ii) receive the second drive data sectors from the non-volatile semiconductor memory.
 17. A method of accessing a non-volatile semiconductor memory, the method comprising: transferring a first block of data during a first data transfer event via an interface module; transferring a second block of data during a second data transfer event via the interface module, wherein the first block of data or the second block of data is non-page based such that a size of the first block of data or a size of the second block of data is not an integer multiple of a page of data; and based on a plurality of descriptors, controlling the first data transfer event and the second data transfer event such that the interface module transfers the first block of data between the interface module and the non-volatile semiconductor memory while transferring the second block of data between the interface module and the non-volatile semiconductor memory, wherein the plurality of descriptors comprise a first descriptor and a second descriptor, wherein the first descriptor includes a first set of instructions for transferring the first block of data, and the second descriptor includes a second set of instructions for transferring the second block of data.
 18. The method of claim 17, wherein each of the first block of data and the second block of data is smaller than a page of data.
 19. The method of claim 17, further comprising, based on the first set of instructions and a third set of instructions, controlling transfer of the first block of data between the interface module and the non-volatile semiconductor memory, wherein: each of the first set of instructions and the third set of instructions includes an address of the first block of data; the first descriptor indicates (i) an amount of data to be transferred during the first data transfer event, or (ii) whether the first data transfer event is a read event or a program event; and the second descriptor indicates (i) an amount of data to be transferred during the second data transfer event, or (ii) whether the second data transfer event is a read event or a program event.
 20. The method of claim 17, further comprising: receiving a plurality of blocks of data; and concurrently transferring the plurality of blocks of data respectively to a plurality of buffers, wherein the plurality of buffers are connected respectively to a plurality of channels of the non-volatile semiconductor memory, and wherein the plurality of blocks of data include the first block of data and the second block of data. 